This invention relates generally to optical components and, more particularly, to adjustable mounting structures for optical components, such as precision mirrors. A laser system typically includes a laser source and an optical beam train, i.e., a series of precision optical components that affect the cross section and direction of the laser beam, as required for a particular application. Highly reflective elements, referred to as mirrors, redirect the beam as needed. The mirrors are mounted on stands that have an angular adjustment capability, usually about two perpendicular axes. The required sensitivity of beam steering must be incorporated into the mirror mount adjustment resolution for each axis. Once a mirror is adjusted to a desired orientation, the mount is locked in position, to restrain the mirror from moving to another position. In some laser systems the mirror mount resolution requirement is less than 20 microradians. This high level of resolution is difficult to achieve and maintain in adverse environments that include vibration, shock loads, acoustic loads fluid flow jitter or thermal loads. In mirror mounts available prior to this invention, the locking mechanisms themselves may induce residual loads in the mirror mount structure, and these induced loads may move the mirror more than 20 microradians. Ideally, therefore, a mirror mount must not only have a high resolution capability, to match the adjustment resolution required for the mirror, but actuation of the locking mechanism must not result in unwanted mirror movement in excess of the resolution requirement. Further, the mount should be resistant to angular movements induced by vibration, shock loads, acoustic loads fluid flow jitter or thermal loads. The present invention is directed to these ends.